JP6708619B2 - Modular portable cask transfer facility - Google Patents

Description

Priority Claim This application benefits from the priority of US Provisional Application No. 62/433,471 filed December 13, 2016. The application is incorporated herein by reference in its entirety.

The present invention relates primarily to apparatus and methods for handling and storing spent nuclear fuel in nuclear power plants.

In nuclear power plants with nuclear reactors, spent nuclear fuel is stored in deep tanks called "spent fuel pools". Fuel has a final closure if the spent fuel pool reaches its spent fuel capacity limit, or if the NPP completes the life of the facility and performs a complete removal of spent fuel from the spent fuel pool. Transferred into a metal canister, the lid is welded closed or sealed by mechanical means after loading the spent fuel at the power plant. The sealed canister is then placed in a concrete storage overpack. The storage overpack acts as an enclosure that provides mechanical protection, heat removal properties, and a radiation shield to the inner metal canister that contains the radioactive material. A concrete overpack includes a canister in which radioactive material is stored, which is then placed outside the nuclear power plant structure but in a designated safe area of land under owner control. , In this case, proper management and monitoring of the concrete storage overpack including the metal canister can be performed more reliably.

The process of removing spent fuel from the spent fuel storage pool, placing spent fuel in metal canisters, and placing metal canisters in concrete storage overpacks involves the use of overhead cranes and associated lifting systems. , Their cranes and systems ensure that positive and safe control of the components being handled is guaranteed during all normal and expected scenarios, including the possibility of earthquakes. , Is thoroughly evaluated and verified before use. The assessments, processes and controls used to ensure that these components are handled safely at nuclear power plants are subject to regulatory investigations and approvals. Furthermore, it is important to note that the concrete storage overpack in which the metal canister is stored only fulfills the regulatory requirements for storage but not for off-site transportation of the canister. is there. The regulations associated with offsite transportation require the use of specially designed offsite transportation casks. The cask is significantly different in design and material from concrete storage overpacks and is licensed for use by regulatory agencies under different legislation than that used to certify concrete storage overpacks.

Near the end of the life of a nuclear power plant, as mentioned above, many owners have chosen to completely remove spent fuel from the spent fuel storage pool and place it in a dry storage concrete overpack, Strive to minimize expenses associated with equipment operation. Once the spent fuel has been relocated, existing equipment may be demolished and removed from the owner's land. When this is achieved, only a concrete or concrete/metal storage overpack is left, which contains a metal canister, within which is spent nuclear fuel and radioactive material. When the need arises to remove the metal canister from the site, the metal canister is transferred from a concrete storage overpack to an offsite shipping cask. However, because the construction, including the overhead crane, has been demolished and removed from the site, there is no provision for facilitating the transfer of metal canisters from concrete storage overpacks to offsite shipping casks.

The present disclosure provides various embodiments of modular portable cask transfer (MPCT) equipment. The MPCT facility can transfer canisters containing spent nuclear fuel from a shipping cask to a storage overpack or from a storage overpack to a shipping cask. The retractable legs allow movement of the transfer cask independent of the canister, which can be moved using a hoist. Due to its modular construction, MPCT equipment can be assembled, disassembled, and moved from one nuclear power plant to another.

In particular, one embodiment is an MPCT installation having a plurality of parallel elongated telescopic leg assemblies. Each leg assembly has an elongated telescopic leg attached to a moveable dolly. Each telescopic leg has a longitudinal body extending from the upper end to the lower end, the lower end being attached to the movable telescopic leg dolly. The upper end can move up and down with respect to the lower end.

The MPCT facility includes multiple parallel elongated lift beams. Each of the lift beams has an elongated body extending from the first end to the second end. Each of the lift beams is supported on the upper ends of the retractable legs and is provided in a direction perpendicular to the retractable legs.

The MPCT facility includes a trolley beam assembly including a movable long trolley beam mounted on a movable trolley beam dolly. The trolley beam has an elongated body extending between the first end and the second end. The trolley beam is supported by the elongate body of the lift beam and is oriented perpendicular to the lift beam.

The MPCT facility includes means for connecting the transfer cask to the trolley beam such that the transfer cask is vertically movable when the upper ends of the retractable legs are moved vertically.

Finally, the MPCT equipment includes a hoist associated with the trolley beam. The hoist is for connecting to the canister and the hoist is for moving the canister vertically. The hoist may be for moving the canister from the storage overpack to the transfer cask or from the transfer cask to the storage overpack. Based on the separate telescopic legs and hoists, the transfer cask and the canister may be vertically movable independently of each other.

In particular another embodiment of the MPCT installation comprises gantry means attached to the transfer cask and for moving the transfer cask vertically and horizontally. In addition, the MPCT equipment has a hoist means associated with the gantry means, which hoist means is moved when the transfer cask is moved vertically and horizontally. The hoist means may be connected to the canister and the hoist means may move the canister vertically independently of the movement of the transfer cask. The hoist means may move the canister from the storage overpack to the transfer cask or from the transfer cask to the storage overpack. It may move the canister from a transport cask to a transfer cask or from a transfer cask to a transport cask.

Other embodiments, methods, apparatus, features and advantages of the invention will be or will be apparent to one with skill in the art upon examination of the following drawings and detailed description. All such additional embodiments, methods, devices, features and advantages are intended to be included herein within the scope of the disclosure and protected by the following claims. Has been done.

Many aspects of the invention can be better understood with reference to the following drawings. The components in the figures are not necessarily to scale and are rather emphasized to clearly explain the principles of the invention. Furthermore, in the drawings, like reference numerals indicate corresponding parts throughout the several views.

FIG. 3 is a perspective view of a modular portable cask transfer (MPCT) facility according to the present disclosure. FIG. 1 shows a transfer cask attempting to meet with a storage overpack below it, for the purpose of passing a canister to or receiving a canister from the storage overpack.

It is a front view of the MPCT equipment of FIG.

It is a right view of the MPCT equipment of FIG.

FIG. 2 is a front view of the MPCT facility of FIG. 1, with a partial cross-sectional view showing a transfer cask associated with a storage overpack and a canister in the transfer cask and above the storage overpack.

FIG. 2 is a front view of the MPCT facility of FIG. 1 with a partial cross-sectional view showing a transfer cask associated with a storage overpack and a canister within the storage overpack and below the transfer cask.

The present disclosure provides various embodiments of a modular portable cask transfer (MPCT) facility 10. 1 to 5 show an example of the MPCT equipment 10. The MPCT facility 10 may be used to transfer canisters containing spent nuclear fuel, such as fuel rods, from a transport cask to a storage overpack or from a storage overpack to a transport cask using a transfer cask, It may also be used for independent protection and management of the canister and transfer cask during the transfer operation, which is important if an earthquake event occurs during the transfer operation. Due to its modular construction, dismantling, moving and reassembling the MPCT facility 10 is easy so that it can be used in multiple nuclear power plants.

Construction and Assembly Unlike conventional gantry cranes, MPCT equipment 10 includes a plurality of parallel elongated telescopic leg assemblies 12 that allow MPCT equipment 10 to move a transfer cask. In this embodiment, there are at least four telescopic leg assemblies. More retractable leg assemblies may be incorporated, depending on the needs of the facility. Each leg assembly 12 has an elongated telescopic leg 14 attached to a moveable dolly 16. Movable dolly 16 is preferably a motor driven, self-propelled and movable side shift dolly, with at least four wheels, controlled by a suitable controller. The dolly 16 rides on or in a track 17 provided along the top surface of an existing storage pad 19. Each retractable leg 14 has a longitudinal body extending from an upper end 14a to a lower end 14b, and the lower end is attached to a movable retractable leg dolly 16. Each elongate body of each telescopic leg 14 has an elongate movable upper outer member mounted around and guided by a stationary lower inner member, where the upper end 14a is vertically movable relative to the lower end 14b. Is. In this example, the upper and lower members have a square cross section. However, the cross section of the assembly may be circular. Further, in the preferred embodiment, the hydraulic system is designed to move the upper end 14a of the telescopic leg 14 up and down relative to the lower end 14b. In other embodiments, a pneumatic system may be used instead of a hydraulic system.

A plurality of parallel elongated lift beams 22, two in this example, are provided on the upper end 14 a of the retractable leg 14. Each of the lift beams 22 has an elongated body extending from the first end 22a to the second end 22b. Each of the lift beams 22 is supported on the upper end 14 a of the retractable leg 14 and is provided in a direction perpendicular to the retractable leg 14.

The trolley beam assembly 24 comprises a movable elongate trolley beam 26 and is attached to a movable trolley beam dolly 28. The moveable trolley beam dolly 28 is preferably a motor driven, self-propelled, movable side shift dolly, with at least four wheels, controlled by a suitable controller. The trolley beam 26 has an elongated body extending between the first end 26a and the second end 26b. The trolley beam 26 is supported by the elongate body of the lift beam 22 and is provided in a direction perpendicular to the lift beam 22.

A plurality of lift links 32 may be used to attach the trolley beam 26 to the transfer cask 34. The transfer cask 34 removes a cylindrical canister 35 (e.g., metal) from a cylindrical storage overpack 37 (e.g., concrete or concrete and metal) held on the storage pad 19, or a cylinder. It can be used to insert a cylindrical canister 35 into a shape storage overpack 37. An example of storage overpack 37 is described in co-pending application No. 14/160,833, filed January 22, 2014, which application is incorporated herein by reference in its entirety. The transfer cask 34 provides protection from harmful radiation by being formed of, for example, metal and other suitable materials, and has a plurality of lift plates 36 attached to the transfer cask 34 to allow the retractable legs to extend. It allows the transfer cask 34 to be lifted and lowered as 14 is lifted and lowered. This embodiment has two lift plates 36 provided on opposite sides of the transfer cask. As shown in FIGS. 4 and 5, the transfer cask 34 has a ring 37 defining an opening or aperture at its upper end and two sliding metal doors 39a and 39b at its lower end. This embodiment of transfer cask 34 is described in more detail in co-pending application No. 14/160,833, filed January 22, 2014, which application is incorporated herein by reference.

The sliding doors 39a and 39b are hydraulically driven or pneumatically driven and slide outward from the transfer cask 34. Welding two "C" shaped channels to the two opposite sides on the underside of the transfer cask 34 captures the side edges of each of the doors 39a and 39b and holds them in place and provides a sliding surface. Can be provided.

A plurality of elongate connectors 38 connect the lift links 32 to the lift plates 36 of the transfer cask 34. The elongated connector 38 may be, for example, a sling (as shown), a fixed rod, a fixed link, or other device, and may be manufactured from a variety of materials, but is preferably metal.

The MPCT equipment 10 further includes a conventional hoist 41, which is preferably a chain hoist with a hook 43. The hook 43 is designed to be connected to the canister lift adapter 42, which is attached to the canister 35. The hook 43 is designed to move the canister 35 up and down independently of the transfer cask 34, and the transfer cask 34 is moved up and down via the telescopic leg 14. The hook 43 mates with the canister lift adapter 42 and is constrained with two mating pins 45a and 45b, which essentially pin the hook 43 to the adapter 42. The hole size at the top of the transfer cask 34 is sufficient for the hooks 43 associated with the hoist 41 to pass through the transfer cask 34.

Instead of a single hoist, a double hoist may be used. Further, in the preferred embodiment, the chain hoist is pneumatic. However, in other embodiments, the hoist may be an electric wire rope hoist or any combination of electrical or pneumatic chains or wire rope hoist systems.

By using a plurality of long seismic resistant rods 44, it is possible to assist in making the MPCT equipment 10 robust. This is due to the structure being more rigid and giving the structure resistance to seismic-induced lateral motion that can overturn the listing configuration. In this example, there are two on each side in a crossed arrangement, each seismic rod 44 being the upper end of a movable outer upper member with one retractable leg 14 and the lower end of another adjacent movable outer upper member of an adjacent leg 14. Or the lower end of one movable outer upper member with one retractable leg 14 and the upper end of another adjacent movable outer upper member of an adjacent leg 14.

For additional seismic stability with respect to the transfer cask 34, the MPCT facility 10 may optionally include a ring 48 surrounding the transfer cask 34, as shown in FIG. 1, which ring 48 and ring 14 respectively. It is supported and held in place by a cable 52 mounted between. In essence, the ring 48 with the cable 52 prevents the transfer cask 34 from rocking horizontally.

Referring to FIG. 1, the transfer adapter 54 is temporarily placed between the transfer cask 34 and the storage overpack 37 as they meet, thereby assisting in supporting the transfer cask 34 and under the transfer cask 34. The opening and closing of the side doors 39a and 39b is assisted. The transfer adapter 54 comprises a generally flat rectangular metal plate having a central hole through which the canister 35 passes. The transfer adapter 54 has index rails 56a and 56b along its side on the plate, which assists in positioning the transfer cask 34 and acts as a guide for the doors 39a and 39b. Transfer adapter 54 has hydraulic or pneumatic cylinders 58a and 58b with corresponding rods 62a and 62b that operate (ie, push and pull) doors 39a and 39b of transfer cask 34, respectively. ).

Utilization and Operation The MPCT facility 10 uses a transfer cask 34 to transfer a canister 35 containing spent nuclear fuel, such as fuel rods, from a transport cask (not shown) to a storage overpack 37 or from a storage overpack 37 to a transport cask. It may also be used for transporting, and may also be used for independent protection and management of the canister 35 and the transport cask 34 during the transporting work, in case of an earthquake event during the transporting work. Is important to.

When the canister 35 is removed from the storage overpack 37 and transferred to a shipping cask, the lid 46 on top of the overpack 37 is removed. The transfer adapter 54 is placed on the storage overpack 37. The transfer cask 34 is then positioned over the storage overpack 37. The doors 39a and 39b of the transfer cask 34 are opened by the transfer adapter 54. The hook 42 of the hoist 41 is lowered through the transport cask 34 and mated with the canister lift adapter 42 using the mating pins 45a and 45b. The canister 35 is lifted vertically from the storage overpack and into the transfer cask 34. The doors 39a and 39b of the transfer cask 34 are closed by the transfer adapter 54. The transfer cask 34 is raised by raising the retractable leg 14.

Place the transfer adapter 54 (or other similar adapter) on the shipping cask. The transport cask is open at its top for receiving the canister 35. The transfer adapter 54 is placed on the shipping cask. The dollies 16 and 28 are used to move the transfer cask 34 with the canister 35 to a position above the transfer adapter above the transfer cask. The doors 39a and 39b of the transfer cask 34 are opened by the transfer adapter 54. The hoist 41 lowers the canister 35 and places it in the transport cask. The hook 43 is disengaged from the transfer adapter 54 by retracting the mating pins 45a and 45b. The hoist 41 raises its hook 43. The door of the transfer cask 34 is closed by the transfer adapter 54. Dolly 16 and 28 are used to move transfer cask 34 away from the shipping cask. Remove the transfer adapter 54.

When moving the canister 35 from the transport cask to the storage overpack 37, the above procedure is simply reversed. Further, the process can be used to transfer a canister from one storage overpack to another storage overpack or to an inspection station located on the same storage pad 19.

Variations and Modifications The above-described embodiments of the present invention, particularly the “preferred” embodiments, are merely possible implementations, merely provided for a clear understanding of the principles of the invention. That should be emphasized. Many variations and modifications may be made to the above-described embodiments of the present invention without departing substantially from the spirit and principles of the invention. All such variations and modifications are intended to be included herein within the scope of the present disclosure.

As a variant, the telescopic leg 14 may have more than two nesting members, ie more members than upper and lower members.

As another example of variation, transfer cask 34, canister 35, and/or storage cask 37 may have other cross-sectional shapes that are not circular, such as square, rectangular, octagonal, etc. It may be used in connection with these.

Claims (19)

A modular portable cask transfer facility for transferring canisters containing spent nuclear fuel from a transport cask to a storage overpack or from a storage overpack to a transport cask using a transfer cask,
A plurality of parallel elongated telescopic leg assemblies, each leg assembly having an elongated telescopic leg attached to a movable dolly, each telescopic leg having a longitudinal body extending from an upper end to a lower end, the lower end Is attached to the movable telescopic leg dolly, the upper end is movable perpendicular to the lower end, a plurality of parallel elongated telescopic leg assembly,
A plurality of parallel elongated lift beams, each of the lift beams having an elongated body extending from a first end to a second end, each of the lift beams being supported at the upper end of the telescopic leg and A plurality of parallel long lift beams provided in a direction perpendicular to the retractable legs,
A trolley beam assembly including a movable elongate trolley beam attached to a movable trolley beam dolly, the trolley beam having an elongated body extending between a first end and a second end, the trolley beam including the lift. A trolley beam assembly supported by the elongate body of the beam and provided in a direction perpendicular to the lift beam;
Means for connecting the transfer cask to the trolley beam such that the transfer cask is vertically movable when the upper end of the telescopic leg is moved vertically.
A hoist associated with the trolley beam, the hoist for connecting to the canister, the hoist for vertically moving the canister, and the hoist for moving the canister. A hoist for moving from a storage overpack to the transfer cask, or from the transfer cask to the storage overpack.
The transfer cask and the canister are vertically movable independently of each other based on the separate telescopic leg and the hoist,
The transfer cask has two sliding metal doors at its lower end,
A transfer adapter is placed between the transfer cask and the storage overpack when the transfer cask meets the transfer cask to assist in supporting the transfer cask,
The transfer adapter have a hydraulic or pneumatic cylinders for opening and closing the two sliding metal doors,
The transfer adapter, the assist positioning of the transfer cask and modular Nomadic cask transfer facility to have a index rail for guiding the two sliding metal doors. Further comprising the transfer cask having a plurality of lift plates on its side surface,
The equipment according to claim 1, wherein the connecting means includes a plurality of lift links attached to the trolley beam, and a plurality of elongated connectors that connect the lift links to the lift plate. The equipment according to claim 2, wherein the long connector is a sling. The facility according to claim 2, wherein the long connector is a fixed link. The facility according to any one of claims 2 to 4, wherein the transfer cask includes a canister containing the spent nuclear fuel. The equipment according to any one of claims 1 to 5, wherein the movable telescopic leg dolly and the movable trolley beam dolly are self-propelled dollies. 7. Equipment according to any one of the preceding claims, further comprising a hydraulic system designed to move the upper end of the retractable leg perpendicular to the lower end. 8. Equipment according to any one of the preceding claims, wherein the telescopic leg assembly comprises four and the lift beams comprise two. The equipment according to any one of claims 1 to 8, wherein the hoist is a pneumatic chain hoist. Each elongate body of each telescopic leg includes an elongate movable outer member disposed around and guided by a stationary inner member, each elongate body further including a plurality of elongate seismic rods, and each seismic rod comprises: Connect the upper end of one movable outer member with one retractable leg to the lower end of another adjacent movable outer member with the next leg, or connect the lower end of one movable outer member with one retractable leg to another of the next leg. The equipment according to any one of claims 1 to 9, which is connected to an upper end of an adjacent movable outer member. A modular portable cask transfer facility for transferring a canister containing spent nuclear fuel from a transport cask to a storage overpack or from a storage overpack to a transport cask, comprising:
A plurality of parallel elongated telescopic leg assemblies, each leg assembly having an elongated telescopic leg attached to a movable dolly, each telescopic leg having a longitudinal body extending from an upper end to a lower end, the lower end Is attached to the movable telescopic leg dolly, the upper end is movable up and down with respect to the lower end, a plurality of parallel elongated telescopic leg assembly,
A plurality of parallel elongated lift beams, each of the lift beams having an elongated body extending from a first end to a second end, each of the lift beams being supported at the upper end of the telescopic leg and A plurality of parallel long lift beams provided in a direction perpendicular to the retractable legs,
A trolley beam assembly including a movable elongate trolley beam attached to a movable trolley beam dolly, the trolley beam having an elongated body extending between a first end and a second end, the trolley beam including the lift. A trolley beam assembly supported by the elongate body of the beam and provided in a direction perpendicular to the lift beam;
A plurality of lift links attached to the trolley beam,
A transfer cask including the canister, wherein the transfer cask is vertically movable when the upper end of the telescopic leg is moved vertically.
A plurality of lift plates attached to the transfer cask,
A plurality of long connectors for connecting the lift link to the lift plate,
A hoist connected to a canister lift adapter, wherein the canister lift adapter is mounted to the canister and is designed to vertically move the canister into or out of the storage overpack independently of the transfer cask. Equipped with a hoist,
The transfer cask has two sliding metal doors at its lower end,
A transfer adapter is placed between the transfer cask and the storage overpack when the transfer cask meets the transfer cask to assist in supporting the transfer cask,
The transfer adapter have a hydraulic or pneumatic cylinders for opening and closing the two sliding metal doors,
The transfer adapter, the assist positioning of the transfer cask and modular Nomadic cask transfer facility to have a index rail for guiding the two sliding metal doors. The equipment according to claim 11 , wherein the movable telescopic leg dolly and the movable trolley beam dolly are self-propelled dollies. 13. Equipment according to claim 11 or 12 , further comprising a hydraulic system designed to move the upper end of the retractable leg perpendicular to the lower end. The equipment according to any one of claims 11 to 13 , wherein the retractable leg assembly includes four and the lift beams include two. The equipment according to any one of claims 11 to 14 , wherein the hoist is a pneumatic chain hoist. Each elongate body of each telescopic leg includes an elongate movable outer member disposed about and guided by a stationary inner member, each elongate body further including a plurality of elongate seismic rods, and each seismic rod comprises: Connect the upper end of one movable outer member with one retractable leg to the lower end of another adjacent movable outer member of the next leg, or connect the lower end of one movable outer member with one retractable leg to another of the next leg. The equipment according to any one of claims 11 to 15 , which is connected to an upper end of an adjacent movable outer member. The equipment according to any one of claims 11 to 16 , wherein the long connector is a sling. The equipment according to any one of claims 11 to 16 , wherein the long connector is a fixed link. A modular portable cask transfer facility for transferring a canister containing spent nuclear fuel from a transport cask to a storage overpack or from a storage overpack to a transport cask using a transfer cask,
Gantry means attached to the transfer cask and for moving the transfer cask vertically and horizontally;
Hoist means associated with the gantry means, the hoist means being moved when the transfer cask is moved in the vertical and horizontal directions.
The hoist means is for connecting to the canister, the hoist means is for vertically moving the canister independently of the movement of the transfer cask, and the hoist means is the canister. From the storage overpack to the transfer cask, or from the transfer cask to the storage overpack, the hoist means moving the canister from the transfer cask to the transfer cask, or the transfer For moving from a cask to the transport cask,
The transfer cask has two sliding metal doors at its lower end,
A transfer adapter is placed between the transfer cask and the storage overpack when the transfer cask meets the transfer cask to assist in supporting the transfer cask,
The transfer adapter have a hydraulic or pneumatic cylinders for opening and closing the two sliding metal doors,
The transfer adapter, the assist positioning of the transfer cask and modular Nomadic cask transfer facility to have a index rail for guiding the two sliding metal doors.

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